Iki weather in May

In May, Iki sees average daytime highs of 19°C and overnight lows near 17°C, with 138 mm of rain across 9.5 wet days and about 13.7 hours of daylight. It is the 6th-warmest and 5th-wettest month of the year here.

Highs climb over the month, from about 18°C in the first days to 20°C by the end. The sky is clear or mostly clear about 33% of the time in May, and the air most often feels comfortable.

Daylight stretches from about 13 h 18 min at the start of May to 14 h 06 min by month's end. Set against the rest of the year, May is Iki's 6th-clearest and 11th-windiest month. For the whole year in context, see Iki's year-round climate.

Daytime high
19°
6th warmest
Overnight low
17°
7th coldest
Rainfall
138 mm
9.5 wet days
Daylight
13 h 42 min
5:25 AM – 7:10 PM
Cloud cover
60%
6th clearest
Wind
20 km/h
11th windiest
Solar energy
5.6 kWh/m²
Travel score
6.1
out of 10

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 18°C in the first days to 20°C by the end.

A typical May day in Iki reaches about 19°C in the afternoon and slips back to 17°C overnight — a 2°C spread between the day's warmth and the night's chill. On most days the high lands between 17°C and 20°C. Set against its neighbours, May runs about 3°C warmer than April and about 3°C cooler than June.

10°15°20°25°151015202531
Avg high (°C)Avg low (°C)
11716
21816
31816
41816
51816
61816
71816
81816
91817
101817
111817
121817
131917
141917
151917
161917
171917
181918
191918
201918
211918
221918
231918
242018
252018
262018
272019
282019
292019
302019
312019

How May really feels in Iki

Once humidity and wind are folded in, May averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

May sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Iki weather by month

How May compares with the rest of the year at a glance. May is the 6th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan10° / 7811.90.5102.2
Feb11° / 7810.20.410.72.4
Mar13° / 10°12611.2011.73.4
Apr16° / 14°13410.1012.84.9
May19° / 17°1389.5013.76.1
Jun22° / 21°25112.6014.25.9
Jul26° / 24°24312.90146.2
Aug27° / 26°15811.2013.36.3
Sep25° / 24°17111.2012.26.6
Oct21° / 20°1007.6011.17.1
Nov17° / 15°979.2010.25.7
Dec13° / 10°79110.29.83.4

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 33% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 11% of May, with mostly cloudy or overcast conditions the remaining 55%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14852
24852
34852
44753
54753
64654
74654
84555
94456
104456
114456
124357
134357
144357
154357
164357
174456
184456
194357
204357
214456
224555
234456
244456
254555
264555
274456
284555
294555
304555
314456

Chance of precipitation in May

Any precipitation

Iki gets around 138 mm of rain over 9.5 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 31% and peaks near 33% on the wettest days.

0%10%20%30%40%151015202531
Rain chance (%)
133
233
333
433
533
633
733
833
933
1033
1133
1233
1333
1432
1532
1632
1731
1831
1930
2030
2130
2229
2329
2429
2528
2628
2728
2828
2928
3028
3128

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

Most of May feels comfortable — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, May lands in the comfortable band about 37% of days. Sticky, muggy-or-worse air turns up on roughly 6% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
14341141
24142152
33943162
43744182
53544192
63345202
73145212
82945232
92846243
102746253
112545263
122445283
132345303
142144323
152043343
161942364
171841384
181639404
191538425
201436445
211335466
221233487
231131517
241030528
25928549
268265610
277245712
287225813
296205915
305195917
314176019

Wind in May

Winds average 20 km/h in May.

Across May, daily wind ranges from about 18 km/h on the calmest days to 21 km/h at its breeziest. It stays fairly steady from day to day.

0510152025151015202531
Wind speed (km/h)Feels
121breezy
221breezy
321breezy
421breezy
521breezy
621breezy
721breezy
821breezy
921breezy
1021breezy
1120breezy
1220breezy
1320breezy
1420breezy
1520light breeze
1620light breeze
1720light breeze
1819light breeze
1919light breeze
2019light breeze
2119light breeze
2219light breeze
2319light breeze
2419light breeze
2519light breeze
2618light breeze
2718light breeze
2818light breeze
2918light breeze
3018light breeze
3118light breeze

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 18 min at the start of May to 14 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 48 minutes over May. Sunrise moves from 5:38 AM to 5:17 AM, and sunset from 6:58 PM to 7:20 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.35:386:58
213.45:376:59
313.45:367:00
413.45:357:01
513.45:347:01
613.55:337:02
713.55:327:03
813.55:327:04
913.65:317:04
1013.65:307:05
1113.65:297:06
1213.65:287:07
1313.75:277:08
1413.75:267:08
1513.75:267:09
1613.75:257:10
1713.85:247:11
1813.85:247:11
1913.85:237:12
2013.85:227:13
2113.95:227:13
2213.95:217:14
2313.95:207:15
2413.95:207:16
2513.95:197:16
2614.05:197:17
2714.05:187:18
2814.05:187:18
2914.05:177:19
3014.05:177:20
3114.15:177:20

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.6 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 2.19 kWh/m² to a high of 5.6 kWh/m² in May across the year — May's 5.6 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.5Bright
25.5Bright
35.5Bright
45.5Bright
55.5Bright
65.5Bright
75.5Bright
85.5Bright
95.5Bright
105.5Bright
115.5Bright
125.5Bright
135.5Bright
145.6Bright
155.6Bright
165.6Bright
175.6Bright
185.6Bright
195.7Bright
205.7Bright
215.7Bright
225.7Bright
235.7Bright
245.7Bright
255.7Bright
265.7Bright
275.7Bright
285.7Bright
295.7Bright
305.6Bright
315.6Bright
Planning a trip in May

Hazard calendar for Iki

In seasonPeak

In May, Iki sits inside its pacific typhoon season. The full year is below, with each hazard's peak months called out.

Iki sits in the Pacific typhoon belt; the season peaks July–October.

Pacific typhoon
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is May a good time to visit Iki?

Our two travel scores rate May for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

6.1
Sightseeing
5th-best month of the year
2.5
Beach & pool
6th-best month of the year

May is a reasonable time to visit Iki for sightseeing.

What to pack for Iki in May

From May's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In May, Iki sees daytime highs around 19°C and nights near 17°C. Worth packing: rain gear and sun protection. About 10 days see rain.

rain gearsun protection

Sea temperature near Iki in May

The nearest coast averages about 18°C in May — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 14 km away) is warmest in August at about 27°C and coldest in February near 15°C.

It's comfortable for a long swim from Jun 6 to Nov 26 — about 5.7 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan16Cool
Feb15Bracing
Mar15Bracing
Apr16Cool
May18Cool
Jun21Refreshing
Jul25Warm
Aug27Warm
Sep26Warm
Oct23Refreshing
Nov21Refreshing
Dec18Cool

UV index in Iki in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Iki peaks around July 23 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highModerateJul 23UV 9Dec 22UV 3
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar6High
Apr8Very high
May8Very high
Jun8Very high
Jul9Very high
Aug9Very high
Sep9Very high
Oct6High
Nov4Moderate
Dec3Moderate

Air quality in Iki in May

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where May falls, not just the annual average.

Air quality in Iki is worst in April — around 24 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (July, 11 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateApr 924 µg/m³Jul 2211 µg/m³
PM2.5 (µg/m³)Level
Jan17Moderate
Feb20Moderate
Mar24Moderate
Apr24Moderate
May21Moderate
Jun16Moderate
Jul11Good
Aug11Good
Sep12Good
Oct11Good
Nov14Moderate
Dec13Moderate
Location & terrain

Where is Iki?

Iki sits at 33.8°N, 129.7°E, 45 m above sea level, in Japan. The nearest listed city is Karatsu, 44 km away.

Topography around Iki

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Iki.

Within 3 km, the terrain around Iki has only modest variations in elevation — a maximum elevation change of 152 m around an average of 64 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 208 m; within 80 km, large variations in elevation — a maximum elevation change of 1,043 m.

The land around Iki is covered by trees (72%) within 3 km, water (83%) within 16 km, and water (77%) within 80 km.

3 km
152 m
16 km
208 m
80 km
1,043 m
treesgrasslandcroplandartificial surfaceswater
May weather nearby: Karatsu 44 km · Hirado 49 km · Matsuura 49 km · Itoshima 51 km · Maebaru-chūō 51 km · Imarichō-kō 58 km · Tsushima 62 km · Shingū 66 km

Japan travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type A / B
100 V · 50 / 60 Hz
Prices
≈ 65% of US
price level, 2025
GDP per capita
$35,951
2025
Happiness
6.1 / 10
World Happiness, 2025
Safe drinking water
99%
of population, 2024
Homicide rate
0.2
per 100k, 2023
Road deaths
3.6
per 100k/yr, 2019
Income group
High
World Bank
English
Very low
EF EPI 446
Religion
Shintoism 49%Buddhism 46%other 4%Christianity 1%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Iki (33.7829°, 129.7209°, elevation 45 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).